268 research outputs found

    Recurso. sIMfLOR – plataforma portuguesa de modelos forestales

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    In the last decades there has been an increasing number of forest models developed for the main species of the Portuguese forest. Forest models support management decisions by predicting long term stand development under alternative scenarios and taking into account all the components of the ecosystem. However, in most cases, there is a gap between the models developed and their application by decision-makers. The platform for Portuguese Forest Simulators (sIMfLOR) tries to overcome this gap integrating a wide variety of forest models into simulators and providing a baseline tool for forest managers in Portugal. As an integrated modular platform, sIMfLOR makes available forest simulators for the Portuguese forest with user-friendly interfaces to facilitate the introduction of the information for the simulators. The platform displays stand and regional simulators, interfaces to generate required inputs and also auxiliary tools. As the platform focus on end-users, it allows visualization of the simulators outputs in default graphics which can easily be edited by users. The sIMfLOR platform can be permanently accessed at http://www.isa.utl.pt/cef/forchange/fctools.En las últimas décadas ha habido un número creciente de modelos forestales desarrollados para las principales especies forestales portuguesas. Los modelos forestales apoyan la toma de decisiones de gestión mediante la predicción del desarrollo a largo plazo de los rodales bajo escenarios alternativos y teniendo en cuenta todos los componentes del ecosistema. Sin embargo, en la mayoría de los casos, existe una brecha entre los modelos desarrollados y su aplicación por los que toman las decisiones. La plataforma portuguesa de simuladores forestales (sIMfLOR) intenta salvar esta brecha integrando una amplia variedad de modelos forestales en simuladores y proporcionando una herramienta de referencia para los gestores forestales en Portugal. Como plataforma modular integrada, sIMfLOR hace accesibles simuladores forestales para los bosques portugueses utilizando interfaces de fácil uso para facilitar la introducción de la información para los simuladores. La plataforma muestra simuladores de rodales y regionales, interfaces para generar insumos necesarios y también herramientas auxiliares. Como el enfoque de la plataforma es en los usuarios finales, permite la visualización de las salidas de los simuladores en gráficos por defecto que pueden ser modificados por los usuarios. A la plataforma sIMfLOR se puede acceder de forma permanente en http://www.isa.utl.pt/cef/forchange/fctools

    Evaluation of spatial and temporal variability of pasture based on topography and the quality of the rainy season

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    Yield and botanical composition of a given dry-land pasture are heavily influenced by rainfall distribution, and vary according to topography. Through analyzing these parameters, it is possible to identify patterns of spatial distribution, related to topographic characteristics, which can be used to improve spatial management of pasture. The main objective of this project was to assess the role of rainfall, temperature and topography in the spatial and temporal variability of pasture and establish models for predicting the spatial distribution and yield of certain plant species, based on its topographic characteristics. This study was carried out over three years, 2004 to 2006, in a dryland pasture located in Southern Portugal. The data obtained were analyzed as a function of distance to flow lines and the results demonstrate that certain topographical characteristics, associated with agronomic information, can be very useful in explaining the spatial and temporal variability of yield and the botanical composition of the pasture. The slope of the linear regression of the variables mentioned can be used to estimate the spatial variation of yield and the botanical composition as a function of distance to flow lines. The regression coefficient can be estimated from the annual rainfall, given the strong correlation between the two

    Evidences for a new role of miR-214 in chondrogenesis

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    miR-214 is known to play a role in mammalian skeletal development through inhibition of osteogenesis and stimulation of osteoclastogenesis, but data regarding other vertebrates, as well as a possible role in chondrogenesis, remain unknown. Here, we show that miR-214 expression is detected in bone and cartilage of zebrafish skeleton, and is downregulated during murine ATDC5 chondrocyte differentiation. Additionally, we observed a conservation of the transcriptional regulation of miR-214 primary transcript Dnm3os in vertebrates, being regulated by Ets1 in ATDC5 chondrogenic cells. Moreover, overexpression of miR-214 in vitro and in vivo mitigated chondrocyte differentiation probably by targeting activating transcription factor 4 (Atf4). Indeed, miR-214 overexpression in vivo hampered cranial cartilage formation of zebrafish and coincided with downregulation of atf4 and of the key chondrogenic players sox9 and col2a1. We show that miR-214 overexpression exerts a negative role in chondrogenesis by impacting on chondrocyte differentiation possibly through conserved mechanisms.Calouste Gulbenkian Foundation (program "Na Fronteira das Ciencias da Vida"); FCT [UID/Multi/04326/2013, PEst-C/MAR/LA0015/2011, SFRH/BD/38607/2007, SFRH/BPD/45034/2008, SFRH/BPD/111289/2015]; European Commission (ERDF-COMPETE) [PEst-C/MAR/LA0015/2011]info:eu-repo/semantics/publishedVersio

    Using continuous measurement to protect a universal set of quantum gates within a perturbed decoherence-free subspace

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    We consider a universal set of quantum gates encoded within a perturbed decoherence-free subspace of four physical qubits. Using second-order perturbation theory and a measuring device modeled by an infinite set of harmonic oscillators, simply coupled to the system, we show that continuous observation of the coupling agent induces inhibition of the decoherence due to spurious perturbations. We thus advance the idea of protecting or even creating a decoherence-free subspace for processing quantum information.Comment: 7 pages, 1 figure. To be published in Journal of Physics A: Mathematical and Genera

    Is the chlorophyll derivative Zn(II)e6Me a good photosensitizer to be used in root canal disinfection?

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    The aim of this study was to assess antimicrobial efficacy and cytotoxic outcomes of a chlorophyll based photosensitizer (PS) Zn(II)chlorin e6 methyl ester (Zn(II)e6Me), when applied to human dentin discs and root blocks infected with 48 h biofilms. The results were compared with the ones obtained with FotoSan® (commercial Toluidine Blue O formulation) and 3% sodium hypochlorite (NaOCl).publishe

    Integrating belowground carbon dynamics into Yield-SAFE, a parameter sparse agroforestry model

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    Agroforestry combines perennial woody elements (e.g. trees) with an agricultural understory (e.g. wheat, pasture) which can also potentially be used by a livestock component. In recent decades, modern agroforestry systems have been proposed at European level as land use alternatives for conventional agricultural systems. The potential range of benefits that modern agroforestry systems can provide includes farm product diversification (food and timber), soil and biodiversity conservation and carbon sequestration, both in woody biomass and the soil. Whilst typically these include benefits such as food and timber provision, potentially, there are benefits in the form of carbon sequestration, both in woody biomass and in the soil. Quantifying the effect of agroforestry systems on soil carbon is important because it is one means by which atmospheric carbon can be sequestered in order to reduce global warming. However, experimental systems that can combine the different alternative features of agroforestry systems are difficult to implement and long-term. For this reason, models are needed to explore these alternatives, in order to determine what benefits different combinations of trees and understory might provide in agroforestry systems. This paper describes the integration of the widely used soil carbon model RothC, a model simulating soil organic carbon turnover, into Yield-SAFE, a parameter sparse model to estimate aboveground biomass in agroforestry systems. The improvement of the Yield-SAFE model focused on the estimation of input plant material into soil (i.e. leaf fall and root mortality) while maintaining the original aspiration for a simple conceptualization of agroforestry modeling, but allowing to feed inputs to a soil carbon module based on RothC. Validation simulations show that the combined model gives predictions consistent with observed data for both SOC dynamics and tree leaf fall. Two case study systems are examined: a cork oak system in South Portugal and a poplar system in the UK, in current and future climate. (c) 2017, Springer Science+Business Media B.V.European Commission through the AGFORWARD FP7 research Project (contract 613520), Forest Research Center strategic Project (PEst OE/AGR/UI0239/2014), the Portuguese Foundation for Science and Technology (FCT) fellowships SFRH/BD/52691/2014 and SFRH/BPD/96475/2013, XUNTA DE GALICIA, Consellería de Cultura, Educación e Ordenación Universitaria (“Programa de axudas á etapa posdoutoral”) (contract ED481B 2016/071-0

    Monitorização de iessotoxinas em mexilhão na Baía de Lisboa

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    [POR] A iessotoxina (YTX) e os seus análogos (YTXs) são compostos lipofílicos, poliéteres de dissulfato, produzidos por microalgas como Protoceratium reticulatum, Lingulodinium polyedrum e Gonyaulax spinifera. Em Portugal, a pesquisa de YTXs iniciou-se em 2005 recorrendo a um kit de imunoiensaio comercial. O presente trabalho teve como objectivo monitorizar a presença de YTXs em mexilhão colhido na Baía de Lisboa, cujo o lado Norte representa uma zona de concentração e retenção de fitoplâncton. Numa tentativa de explicar a persistência da concentração de iessotoxina em mexilhão realizou-se em laboratório um estudo de destoxificação. Na Baía de Lisboa, o mexilhão apresentou contaminação com YTXs de Maio a Dezembro de 2005 com dois picos máximos, um em Junho com 1.53 mg Kg-1 e outro em Agosto com 1.42 mg Kg-1. Os valores máximos de YTXs foram simultâneos com a presença de Lingulodinium polyedrum na água, embora em baixas concentrações. Os ensaios laboratoriais de destoxificação evidenciaram uma lenta eliminação desta toxina o que explica a persistência de YTXs no mexilhão até ao final de 2005. O facto de as elevadas concentrações de YTXs terem sido registadas quando houve baixas concentrações de células na água pode também estar relacionado com a lenta eliminação destas toxinas. [ESP] La iessotoxina (YTX) y sus análogos (YTX) son compuestos poliéteres de disulfato lipofílicos, producidos por microalgas como Protoceratium reticulatum, Lingulodinium polyedrum y Gonyaulax spinifera. En Portugal, la investigación sobre YTX comenzó en 2005 utilizando a un kit de inmunoensayo comercial. El presente trabajo tuvo objetivo monitorear la presencia de YTXs en mejillones cosechados en la Bahía de Lisboa, cuyo lado norte representa una zona de concentración y retención de fitoplancton. En un intento de explicar la persistencia de la concentración de iessotoxina en mejillones, un estudio de laboratorio de desintoxicación En la Bahía de Lisboa, el mejillón presentó contaminación con YTXs de mayo a diciembre de 2005 con dos picos máximos, uno en junio con 1,53 mg Kg-1 y otro en agosto con 1,42 mg Kg-1. Los valores los YTX máximos fueron simultáneos con la presencia de Lingulodinium poliedro en agua, aunque en bajas concentraciones. Los exámenes laboratorio de desintoxicación evidenció una eliminación lenta de este toxina que explica la persistencia de YTXs en mejillones hasta el final de 2005. El hecho de que se registraran altas concentraciones de YTX cuando había bajas concentraciones de células en el agua también puede ser relacionados con la lenta eliminación de estas toxinas.Este trabalho foi suportado pelos programas QCAIII /med.4/ MARE – Segurança, Vigilância e Qualidade dos Moluscos Bivalves e QCAIII/POPesca/MARE – Caracterização ecológica da zona costeira – Plataforma Continental. Os autores agradecem a disponibilidade demonstrada pelos técnicos do Departamento de Aquacultura, IPIMAR

    Avaliação da variabilidade das características do solo numa pastagem permanente integrada num projecto de Agricultura de Precisão

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    O levantamento da variabilidade do solo e da vegetação numa pastagem permanente é a base para a gestão diferenciada da fertilização, a qual é o principal instrumento utilizado pelos agricultores na melhoria das pastagens permanentes no Alentejo. O processo tradicional de amostragem e avaliação das características do solo é muito exigente em termos de tempo, de reagentes necessários nas análises e de trabalho manual, o que pode comprometer um projecto de agricultura de precisão. Este artigo descreve as principais etapas seguidas pelos autores para simplificar a metodologia de avaliação do solo em pastagens permanentes, baseada na utilização de uma sonda de condutividade eléctrica num projecto de agricultura de precisão. Os ensaios decorreram numa parcela de cerca de 6 hectares, a qual foi subdividida em quadrículas de 28m por 28m. As amostras de solo e a avaliação da condutividade eléctrica foram georeferenciadas com o Sistema de Posicionamento Global (GPS). Os dados geoespaciais foram tratados pelo software ArcGis 9.3 e foi utilizada a análise de regressão ponderada geograficamente (Geographically Weighted Regression) obtendo-se valores de coeficientes de determinação interessantes entre o pH e a condutividade eléctrica e ainda entre esta última e a produtividade da pastagem, em termos de matéria seca

    Farmers’ reasoning behind the uptake of agroforestry practices: evidence from multiple case-studies across Europe

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    Potential benefits and costs of agroforestry practices have been analysed by experts, but few studies have captured farmers’ perspectives on why agroforestry might be adopted on a European scale. This study provides answers to this question, through an analysis of 183 farmer interviews in 14 case study systems in eight European countries. The study systems included high natural and cultural value agroforestry systems, silvoarable systems, high value tree systems, and silvopasture systems, as well as systems where no agroforestry practices were occurring. A mixed method approach combining quantitative and qualitative approaches was taken throughout the interviews. Narrative thematic data analysis was performed. Data collection proceeded until no new themes emerged. Within a given case study, i.e. the different systems in different European regions, this sampling was performed both for farmers who practice agroforestry and farmers who did not. Results point to a great diversity of agroforestry practices, although many of the farmers are not aware of the term or concept of agroforestry, despite implementing the practice in their own farms. While only a few farmers mentioned eligibility for direct payments in the CAP as the main reason to remove trees from their land, to avoid the reduction of the funded area, the tradition in the family or the region, learning from others, and increasing the diversification of products play the most important role in adopting or not agroforestry systems
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